Synchronizing Rolling Shutter and Global Shutter Sensors

ABSTRACT

An imaging system for synchronizing rolling shutter and global shutter sensors is disclosed herein. An example imaging system includes an illumination source configured to emit illumination lasting a predetermined period, a first imaging sensor, and a second imaging sensor. The first imaging sensor is configured to capture first image data representative of an environment appearing within a field of view (FOV) of the first imaging sensor during a first period that overlaps at least partially with the predetermined period, and the first imaging sensor operates as a global shutter imaging sensor. The second imaging sensor is configured to capture second image data representative of an environment appearing within a FOV of the second imaging sensor during a second period that overlaps at least partially with the predetermined period and is different from the first period, and the second imaging sensor operates as a rolling shutter imaging sensor.

BACKGROUND

Barcode scanning devices that include visual imaging systems arecommonly utilized in many retail and other locations. Such devicestypically include multiple global imaging shutters to expose imagingsensors for the barcode scanning function and the visual imagingfunction. However, this double global shutter configuration increasesthe complexity and cost of such devices as each global shutter requiresan external imaging processor. This conventional configuration alsoinherently limits the effectiveness of emitted illumination from anillumination source because the global shutters combined exposure periodis only a fraction of the period during which the illumination ispresent. Consequently, conventional barcode scanning devices thatinclude visual imaging systems suffer from multiple issues that causesuch conventional devices to operate non-optimally for functions such asobject recognition.

Accordingly, there is a need for barcode scanning devices with visualimaging systems that synchronize rolling shutter and global shuttersensors in order to optimize the performance of the barcode scanning andvisual imaging functions relative to conventional devices.

SUMMARY

Generally speaking, the imaging systems herein utilize multiple imagingsensors and an illumination source to capture image data usingillumination from the illumination source. In particular, the firstimaging sensor may operate as a global shutter imaging sensor that isconfigured to expose all photosites simultaneously and/or nearlysimultaneously to capture image data, and the second imaging sensor mayoperate as a rolling shutter imaging sensor that is configured to exposeindividual rows/columns of photosites sequentially to capture imagedata. The imaging sensors may be configured to capture image data duringa predetermined period, and the periods within the predetermined periodduring which the respective imaging sensors capture image data may bedifferent.

Accordingly, in an embodiment, the present invention is an imagingsystem for reading and/or decoding indicia. The imaging systemcomprises: an illumination source configured to emit illuminationlasting a predetermined period; a first imaging sensor configured tocapture first image data representative of an environment appearingwithin a field of view (FOV) of the first imaging sensor during a firstperiod that overlaps at least partially with the predetermined period,the first imaging sensor operating as a global shutter imaging sensor;and a second imaging sensor configured to capture second image datarepresentative of an environment appearing within a FOV of the secondimaging sensor during a second period that overlaps at least partiallywith the predetermined period and is different from the first period,the second imaging sensor operating as a rolling shutter imaging sensor.

In a variation of this embodiment, an initial exposure of the firstimaging sensor is within 2 milliseconds (ms) of a beginning of thepredetermined period, and an initial exposure of the second imagingsensor is within 2 ms of an end of the first period.

In another variation of this embodiment, a first sensor readout periodof the first imaging sensor and a second sensor readout period of thesecond imaging sensor take place at least partially within thepredetermined period.

In yet another variation of this embodiment, a beginning of a subsequentimage data capture of the first imaging sensor is within 2 milliseconds(ms) of an end of the second period.

In yet another variation of this embodiment, the imaging system furthercomprises: a first imaging apparatus that includes the first imagingsensor, and wherein, responsive to the second period ending at leastpartially outside of the predetermined period, the first imagingapparatus receives a delay signal to delay exposure of the first imagingsensor until the second imaging sensor is not exposed.

In still another variation of this embodiment, the second imaging sensoris further configured to capture subsequent image data representative ofthe environment appearing within the FOV of the second imaging sensorduring a subsequent period that is different from the second period, thesecond imaging sensor operating as a global shutter imaging sensorduring the subsequent period.

In yet another variation of this embodiment, the second period at leastpartially overlaps with the first period.

In still another variation of this embodiment, the second periodcorresponds with a central period of the predetermined period that doesnot include the first period.

In yet another variation of this embodiment, the first period beginswithin 2 milliseconds (ms) of the second period, and image data capturedby a set of initially exposed sensor rows of the second imaging sensoris discarded during a second imaging sensor readout period within thepredetermined period.

In still another variation of this embodiment, the first period beginswithin 2 milliseconds (ms) of the second period, the FOV of the secondimaging sensor is larger than the FOV of the first imaging sensor, and aportion of the emitted illumination is clipped to avoid illuminating aset of initially exposed sensor rows of the second imaging sensor thatare along an edge of the FOV of the second imaging sensor.

In yet another variation of this embodiment, the first period beginswithin 2 milliseconds (ms) of an end of the second period, the FOV ofthe second imaging sensor is larger than the FOV of the first imagingsensor, and a portion of the emitted illumination is clipped to avoidilluminating a set of finally exposed sensor rows of the second imagingsensor that are along an edge of the FOV of the second imaging sensor.

In another embodiment, the present invention is a tangiblemachine-readable medium comprising instructions for reading and/ordecoding indicia that, when executed, cause a machine to at least: emitillumination lasting a predetermined period; expose a first imagingsensor for a first period that overlaps at least partially with thepredetermined period, the first imaging sensor operating as a globalshutter imaging sensor; capture, by the first imaging sensor, firstimage data representative of an environment appearing within a field ofview (FOV) of the first imaging sensor during the first period; expose asecond imaging sensor for a second period that overlaps at leastpartially with the predetermined period and is different from the firstperiod, the second imaging sensor operating as a rolling shutter imagingsensor; and capture, by the second imaging sensor, second image datarepresentative of an environment appearing within a FOV of the secondimaging sensor.

In a variation of this embodiment, the instructions, when executed,further cause the machine to at least: begin exposing the first imagingsensor within 2 milliseconds (ms) of a beginning of the predeterminedperiod; and begin exposing the second imaging sensor within 2 ms of anend of the first period.

In another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: cause a first sensorreadout period of the first imaging sensor and a second sensor readoutperiod of the second sensor to take place at least partially within thepredetermined period.

In yet another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: begin capturing, by thefirst imaging sensor, subsequent image data within 2 milliseconds (ms)of an end of the second period.

In still another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: responsive to thesecond period ending at least partially outside of the predeterminedperiod, delay exposure of the first imaging sensor until the secondimaging sensor is not exposed.

In yet another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: cause the secondimaging sensor to capture subsequent image data representative of theenvironment appearing within the FOV of the second imaging sensor duringa subsequent period that is different from the second period, the secondimaging sensor operating as a global shutter imaging sensor during thesubsequent period.

In still another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: expose the secondimaging sensor at least partially during the first period, such that thesecond period at least partially overlaps with the first period.

In yet another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: expose the secondimaging sensor such that the second period corresponds with a centralperiod of the predetermined period that does not include the firstperiod.

In still another variation of this embodiment, the instructions, whenexecuted, further cause the machine to at least: cause the first periodto begin within 2 milliseconds (ms) of the second period; and discardimage data captured by a set of initially exposed sensor rows of thesecond imaging sensor during a second sensor readout period within thepredetermined period.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying figures, where like reference numerals refer toidentical or functionally similar elements throughout the separateviews, together with the detailed description below, are incorporated inand form part of the specification, and serve to further illustrateembodiments of concepts that include the claimed invention, and explainvarious principles and advantages of those embodiments.

FIG. 1 is a perspective view of a prior art bioptic barcode reader,implemented in a prior art point-of-sale (POS) system, showing captureof an image of a target object.

FIG. 2A illustrates a profile view of an example imaging system thatincludes a first imaging apparatus, a second imaging apparatus, and anillumination source, in accordance with embodiments disclosed herein.

FIG. 2B is a block diagram of an example logic circuit for implementingexample methods and/or operations described herein.

FIG. 3A is a graph illustrating a prior art activation sequence ofmultiple image sensors in a prior art barcode reader.

FIG. 3B is a graph illustrating a first exemplary activation sequence ofthe illumination source, a first imaging sensor, and a second imagingsensor, in accordance with embodiments disclosed herein.

FIG. 3C is a graph illustrating a second exemplary activation sequenceof the illumination source, the first imaging sensor, and the secondimaging sensor, in accordance with embodiments disclosed herein.

FIG. 3D is a graph illustrating a third exemplary activation sequence ofthe illumination source, the first imaging sensor, and the secondimaging sensor, in accordance with embodiments disclosed herein.

FIG. 3E is a graph illustrating a fourth exemplary activation sequenceof the illumination source, the first imaging sensor, and the secondimaging sensor, in accordance with embodiments disclosed herein.

FIG. 3F is a graph illustrating a fifth exemplary activation sequence ofthe illumination source, the first imaging sensor, and the secondimaging sensor, in accordance with embodiments disclosed herein.

FIG. 4 illustrates an example method for capturing image data by a firstimaging sensor and a second imaging sensor using illumination emitted byan illumination source, in accordance with embodiments disclosed herein.

Skilled artisans will appreciate that elements in the figures areillustrated for simplicity and clarity and have not necessarily beendrawn to scale. For example, the dimensions of some of the elements inthe figures may be exaggerated relative to other elements to help toimprove understanding of embodiments of the present invention.

The apparatus and method components have been represented whereappropriate by conventional symbols in the drawings, showing only thosespecific details that are pertinent to understanding the embodiments ofthe present invention so as not to obscure the disclosure with detailsthat will be readily apparent to those of ordinary skill in the arthaving the benefit of the description herein.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a prior art bioptic barcode reader 100,implemented in a prior art point-of-sale (POS) system 102, showingcapture of an image of a target object 104 being swiped across thebioptic barcode reader 100 scanning area. The POS system 102 includes aworkstation 106 with a counter 108, and the bioptic barcode reader 100.The bioptic barcode reader 100 includes a weighing platter 110, whichmay be a removable or a non-removable. Typically, a customer or storeclerk will pass the target object 104 across at least one of asubstantially vertical imaging window 112 or a substantially horizontalimaging window 114 to enable the bioptic barcode reader 100 to captureone or more images of the target object 104, including the barcode 116.

As part of the clerk passing the target object 104 across the imagingwindows 112, 114, the bioptic barcode reader 100 may triggerillumination sources 120 a, 120 b included in the reader 100 to emitillumination, and for one or more imaging sensors 122 a, 122 b tocapture image data of the target object 104 and/or the barcode 116. Theillumination sources 120 a, 120 b may emit different illumination (e.g.,white light, red light, etc.) depending on the imaging sensor currentlyconfigured to capture image data. Moreover, the imaging sensors 120 a,120 b may both operate as global shutter imaging sensors when therespective illumination source 122 a, 122 b emits illumination for therespective imaging sensor 120 a, 120 b.

For example, a first illumination source 120 a may emit red light toilluminate the target object 104 when a barcode scanning sensor 122 a isactivated to capture image data, and a second illumination source 120 bmay emit white light to illuminate the target object 104 when a visualimaging sensor 122 b is activated to capture image data. When the firstillumination source 120 a emits the red light illumination, the secondillumination source 120 b may not emit white light illumination, and thevisual imaging sensor 122 b may not capture image data. Conversely, whenthe second illumination source 120 b emits white light illumination, thefirst illumination source 120 a may not emit the red light illumination,and the barcode scanning sensor 122 a may not capture image data.

More specifically, the first illumination source 120 a may includemultiple red light emitting diodes (LEDs) on each side of the barcodescanning sensor 122 a, and the second illumination source 120 b mayinclude multiple white LEDs on each side of the visual imaging sensor122 b. When a clerk or customer passes the target object 104 in front ofeither scanning window 112, 114, the bioptic barcode reader 100 mayactivate the first illumination source 120 a to emit red lightillumination, and the reader 100 may activate the barcode scanningsensor 122 a to capture image data of the barcode 116. Once the barcodescanning sensor 122 a has captured image data of the barcode 116, thereader 100 may deactivate the first illumination source 120 a and mayactivate the second illumination source 120 b to emit white lightillumination. Accordingly, the reader 100 may also activate the visualimaging sensor 122 b to capture image data of the target object 104using the white light illumination from the second illumination source120 b.

However, as previously mentioned, this conventional activation sequenceinvolving multiple global shutter imaging sensors (e.g., imaging sensors120 a, 120 b) yields several undesirable results. Namely, conventionaldevices similar to the prior art bioptic barcode reader 100 suffer fromincreased complexity and cost as each global shutter imaging sensorrequires an external imaging processor. This conventional configurationalso inherently limits the effectiveness of emitted illumination fromthe illumination sources (e.g., illumination sources 122 a, 122 b)because the combined exposure period of the global shutter imagingsensors (120 a, 120 b) is only a fraction of the period during which theillumination is present. Moreover, the prior art bioptic barcode reader100 also suffers from less effective imaging tasks, such as objectrecognition, that typically benefit from the additional sharpnessyielded from longer exposure times than global shutter imaging sensorsutilize.

More specifically, conventional devices suffer from requiring multipleglobal shutter imaging sensors due to the contrasting imagingrequirements and corresponding end goals of barcode scanners and visualimagers. Barcode imagers typically include monochromatic sensorsconfigured to operate with relatively short exposure periods that freezean indicia in place during image capture (e.g., minimizing blur) withoutsacrificing a sufficiently high number of pixels per module (PPM) inorder to accurately decode the indicia payload. On the other hand,visual imagers typically include color sensors configured to operatewith relatively longer exposure periods in order to acquire sufficientcolor data and brightness to perform accurate image analysis that doesnot necessarily require negligible image blur. Thus, these differencesresult in at least the visual imaging tasks suffering from the use ofglobal shutter imaging sensors, as such shutters can fail to captureimages with sufficient quality in order to perform many of the visualimaging tasks. However, to resolve these issues with conventionaldevices, the imaging systems of the present disclosure provide a firstimaging sensor that operates as a global shutter imaging sensor and asecond imaging sensor that operates as a rolling shutter imaging sensor,such that the imaging systems of the present disclosure are suitable forbarcode decoding as well as visual image analysis.

To illustrate, FIG. 2A provides a profile view of an example imagingsystem 200 that includes a first imaging apparatus 202, a second imagingapparatus 204, and an illumination source 206, in accordance withembodiments disclosed herein. The example imaging system 200 may be anysuitable type of imaging device, such as a bioptic barcode scanner, aslot scanner, an original equipment manufacturer (OEM) scanner inside ofa kiosk, a handle/handheld scanner, and/or any other suitable imagingdevice type. For ease of discussion only, the example imaging system 200may be described herein as a vertical imaging tower of a bioptic barcodescanner.

Generally speaking, the first imaging apparatus 202 may be a barcodescanner with one or more barcode imaging sensors that operate as globalshutter imaging sensors and that are configured to capture image datarepresentative of an environment appearing within a field of view (FOV)202 a of the first imaging apparatus 202, such as one or more images ofan indicia associated with the target object. The second imagingapparatus 204 may be visual imager (also referenced herein as a “visioncamera”) with one or more visual imaging sensors that operate as rollingshutter imaging sensors and that are configured to capture image datarepresentative of an environment appearing within a FOV 204 a of thesecond imaging apparatus 204, such as one or more images of a targetobject.

The illumination source 206 may generally be configured to emit anillumination pulse that provides illumination during a predeterminedperiod. The first imaging apparatus 202 and the second imaging apparatus204 may be configured to capture image data during the predeterminedperiod, thereby utilizing at least some of the same illuminationprovided by the illumination pulse emitted from the illumination source206. In some embodiments, the first imaging apparatus 202 and the secondimaging apparatus 204 may use and/or include color sensors and theillumination source 206 may emit white light illumination via theillumination pulse. Additionally, or alternatively, the second imagingapparatus 204 may use and/or include a monochrome sensor configured tocapture image data of an indicia associated with the target object in aparticular wavelength or wavelength range (e.g., 600 nanometers(nm)-700nm).

More specifically, the first imaging apparatus 202 and the secondimaging apparatus 204 may each include subcomponents, such as one ormore imaging sensors (e.g., first imaging sensor 202 b, second imagingsensor 204 b in FIG. 2B) and/or one or more imaging shutters (not shown)that are configured to enable the imaging apparatuses 202, 204 tocapture image data corresponding to, for example, a target object and/oran indicia associated with the target object. It should be appreciatedthat the imaging shutters included as part of the imaging apparatuses202, 204 may be electronic and/or mechanical shutters configured toexpose/shield the imaging sensors of the apparatuses 202, 204 from theexternal environment. In particular, the imaging shutters that may beincluded as part of the imaging apparatuses 202, 204 may function aselectronic shutters that clear photosites of the imaging sensors at abeginning of an exposure period of the respective sensors.

Regardless, such image data may comprise 1-dimensional (1D) and/or2-dimensional (2D) images of a target object, including, for example,packages, products, or other target objects that may or may not includebarcodes, QR codes, or other such labels for identifying such packages,products, or other target objects, which may be, in some examples,merchandise available at retail/wholesale store, facility, or the like.A processor (e.g., processor 212 of FIG. 2B) of the example imagingsystem 200 may thereafter analyze the image data of target objectsand/or indicia passing through a scanning area or scan volume of theexample imaging system 200.

The first imaging apparatus 202 may have a first field of view (FOV) 202a, and the second imaging apparatus 204 may have a second FOV 204 a thatat least partially overlaps the first FOV 202 a. As illustrated in FIG.2A, the first FOV 202 a and the second FOV 204 a may include differentportions of the external environment of the example imaging system 200.For example, the second FOV 204 a may extend above/below the first FOV202 a, and as a result, the second imaging apparatus 204 may captureimage data of a portion of the external environment that the firstimaging apparatus 202 may not capture. Of course, it will be appreciatedthat the FOV 202 a, 204 a of the respective imaging apparatuses 202, 204may be of any suitable size and provide any suitable coverage tofacilitate the functionalities described herein.

These differences in the FOVs 202 a, 204 a may be benefit the respectiveimaging apparatuses 202, 204. Namely, the first FOV 202 a may beoriented and sized such that the images captured by the first imagingapparatus 202 have sufficient resolution to successfully decode barcodesand/or other indicia (e.g., quick response (QR) codes, etc.) included inthe image data. Similarly, the second FOV 204 a may be oriented andsized appropriately to optimize the captured images for a visionapplication performed by the example imaging system 200. For example,the second imaging apparatus 204 may capture images that are intended tobe utilized by the example imaging system 200 for at least one of: (i)facial recognition, (ii) scan avoidance detection, (iii) ticketswitching detection, (iv) item recognition, or (v) video feed analysis.

Typically, the second FOV 204 a may be larger than the first FOV 202 abecause the second imaging apparatus 204 may not require the same levelof resolution in captured images as the first imaging apparatus 202. Inparticular, unlike the image data captured by the first imagingapparatus 202, the image data captured by the second imaging apparatus204 is not typically evaluated for decoding of indicia. Thus, as anexample, the second FOV 204 a may be or include a relatively largeregion of the external environment in order to acquire enough visualdata that would enable the example imaging system 200 to perform scanavoidance detection (e.g., clerk or customer pretending to scan an itemwithout actually passing the indicia associated with the item across thescanning windows or FOVs). As another example, the second FOV 204 a maybe relatively large to enable the example imaging system 200 to performproduct identification for large items or to enable multiple differentfocuses depending on the item of interest.

As mentioned, the illumination source 206 may generally emitillumination pulses within a wavelength range generally corresponding towhite light illumination. For example, each illumination pulse mayinclude light within a wavelength range generally extending from about400 nm to about 700 nm. Generally, as previously mentioned, theillumination source 206 may emit an illumination pulse, and theillumination pulse may last for a predefined period. During thepredefined period, both the first imaging apparatus 202 and the secondimaging apparatus 204 may proceed to capture image data corresponding tothe target object and/or the indicia associated with the target object.Thus, the imaging shutters for both the first imaging apparatus 202 andthe second imaging apparatus 204 may be configured to expose the firstimaging apparatus 202 and the second imaging apparatus 204 while anillumination pulse provides illumination defining a single predefinedperiod.

As an example, a clerk may bring a target object into the FOVs 202 a,204 a of the imaging apparatuses 202, 204, and the example imagingsystem 200 may cause the illumination source 206 to emit an illuminationpulse, thereby providing illumination lasting a predefined period. Theimaging shutter of the second imaging apparatus 204 may expose theimaging sensors of the second imaging apparatus 204 (e.g., clearphotosites of the second imaging sensor) when the illumination source206 emits the illumination pulse in order for the second imagingapparatus 204 to capture image data corresponding to, for example, thetarget object within the FOV 204 a. In certain instances, the imagingshutter of the second imaging apparatus 204 may, for example, expose theimaging sensors of the second imaging apparatus 204 slightly after theillumination source 206 emits the illumination pulse, but while theillumination pulse continues to provide illumination sufficient toenable the second imaging apparatus 204 to capture image data.

Further, the imaging shutter of the first imaging apparatus 202 mayexpose the imaging sensors of the first imaging apparatus 202 (e.g.,clear photosites of the first imaging sensor) nearly simultaneously withthe illumination source 206 emitting the illumination pulse. Moreover,both imaging apparatuses 202, 204 may conclude respective exposureswithin the predetermined period, such that the image data captured byboth apparatuses 202, 204 received constant illumination from the singleillumination pulse. In this manner, both imaging apparatuses 202, 204may capture image data during the image capture duration using theillumination provided by a single illumination pulse emitted from theillumination source 206.

In certain embodiments, the duration of the predetermined period may bebased on the exposure period requirements of the respective apparatuses202, 204. For example, the first imaging apparatus 202 may have arelatively short exposure requirement in order to achieve the necessaryresolution for decoding an indicia associated with a target object. Bycontrast, the second imaging apparatus 204 may have a relatively longexposure requirement in order to achieve the necessary color andbrightness to perform object recognition and/or other visual analysistasks (e.g., facial recognition, scan avoidance detection, ticketswitching detection, item recognition, video feed analysis, etc.). Thus,in these embodiments, the predetermined period may be long enough suchthat the exposure period of the second imaging apparatus 204 may fitentirely within the predetermined period.

Additionally, or alternatively, the illumination source 206 may emitindividual illumination pulses for each imaging apparatus 202, 204, andthe individual illumination pulses may define predetermined periods ofdifferent lengths based on the exposure periods of the respectiveimaging apparatuses 202, 204. For example, the illumination source 206may emit a first illumination pulse that provides illumination lasting afirst predetermined period, and the imaging shutter for the firstimaging apparatus 202 may expose the first imaging sensors of the firstimaging apparatus 202 during the first predetermined period to captureimage data corresponding to an indicia associated with a target object.When the first illumination pulse stops providing illumination, theillumination source 206 may emit a second illumination pulse thatprovides illumination lasting a second predetermined period, and theimaging shutter for the second imaging apparatus 204 may expose thesecond imaging sensors of the second imaging apparatus 204 during thesecond predetermined period to capture image data corresponding to thetarget object.

In some embodiments, the first imaging apparatus 202 and/or the secondimaging apparatus 204 may generate and transmit a signal to theillumination source 206 to cause the source 206 to emit illuminationpulses in synchronization with an exposure period of the first imagingapparatus 202 and/or the second imaging apparatus 204. For example, thesecond imaging apparatus 204 may generate and transmit a signal to theillumination source 206 indicating that the apparatus 204 has anexposure period that is longer than the exposure period of the firstimaging apparatus 202. As a result, the illumination source 206 mayadjust the emission time of the illumination pulse to ensure that theexposure period of the second imaging apparatus 204 falls entirelywithin the predefined period defined by the illumination pulse.Additionally, or alternatively, the signal transmitted to theillumination source 206 may indicate that the first imaging apparatus202 and/or the second imaging apparatus 204 is configured to captureimage data (e.g., expose) during a start time and an end time, duringwhich, the illumination source 206 is not configured to emit anillumination pulse. Responsive to receiving the signal, the illuminationsource 206 may emit an illumination pulse at the start time of theexposure period for the respective imaging apparatus 202, 204 to ensurethat the respective imaging apparatus 202, 204 has adequate illuminationwhile capturing image data. This may be of particular use, for example,when the first imaging apparatus 202, the second imaging apparatus 204,and/or any other imaging apparatus is an external imaging apparatus thatis not included within a housing of the example imaging system 200.

Moreover, in certain embodiments, the illumination source 206 maytrigger the exposure of the first imaging apparatus 202 and/or thesecond imaging apparatus 204. For example, the illumination source 206may emit an illumination pulse, and simultaneously send an activationsignal to the first imaging apparatus 202 and/or the second imagingapparatus 204 in order to cause either or both apparatuses to captureimage data during the predetermined period. The illumination source 206may cause both imaging apparatuses 202, 204 to expose simultaneously,and/or the source 206 may send two signals during the image captureduration to stagger the exposure of the apparatuses 202, 204 during theimage capture duration. For example, the illumination source 206 maytransmit a first activation signal to the first imaging apparatus 202simultaneously with the emission of the illumination pulse, and thesource 206 may transmit a second activation signal to the second imagingapparatus 204 sometime after the first activation signal but stillwithin the predetermined period defined by the illumination pulse.

Additionally, or alternatively, in certain embodiments, the exposureperiods for one or both of the imaging apparatuses 202, 204 may exceedthe predetermined period. The predetermined period may not provide oneor both of the imaging apparatuses 202, 204 adequate time to capture theimage data, and as a result, one or both of the imaging apparatuses 202,204 may need to expose for a duration that extends beyond/before thepredetermined period to ensure the imaging sensors are adequatelyexposed to the external environment. For example, the second imagingapparatus 204 may begin exposure after the first imaging apparatus 202,and may require a longer exposure period than the first imagingapparatus 202. The second imaging apparatus 204 may continue exposingthe imaging sensors after the illumination from the illumination pulsehas ceased, and the imaging sensors of the second imaging apparatus 204may rely on ambient illumination to provide further illumination duringthe remaining exposure. As another example, the first imaging apparatus202 may begin exposure to the external environment before theillumination source 206 emits an illumination pulse. Thus, the firstimaging apparatus 202 may also rely, in part, on ambient light toprovide illumination during an exposure period of the imaging sensors ofthe first imaging apparatus 202.

In some embodiments, the illumination source 206 may include multipleLEDs and multiple lenses in order to provide optimal illumination forthe first imaging apparatus 202 and the second imaging apparatus 204.Some of the multiple lenses and/or the multiple LEDs may be optimallyconfigured to provide illumination for the first imaging apparatus 202,such that some/all of the first FOV 202 a is illuminated with light thatoptimally illuminates, for example, an indicia associated with a targetobject for indicia payload decoding. Similarly, some of the multiplelenses and/or the multiple LEDs may be optimally configured to provideillumination for the second imaging apparatus 204, such that some/all ofthe second FOV 204 a is illuminated with light that optimallyilluminates, for example, a target object for various visual analysistasks. For example, when emitting an illumination pulse, during which,the first imaging apparatus 202 is exposed to capture image data, theillumination source 206 may utilize a first LED and a first lens toilluminate the first FOV 202 a. When emitting an illumination pulse,during which, the second imaging apparatus 204 is exposed to captureimage data, the illumination source 206 may utilize the first LED, asecond LED, a third LED, and a second lens to illuminate the second FOV204 a.

FIG. 2B is a block diagram representative of an example logic circuitcapable of implementing, for example, one or more components of theexample imaging system 200 of FIG. 2A. The example logic circuit of FIG.2B is a processing platform 210 capable of executing instructions to,for example, implement operations of the example methods describedherein, as may be represented by the flowcharts of the drawings thataccompany this description. Other example logic circuits capable of, forexample, implementing operations of the example methods described hereininclude field programmable gate arrays (FPGAs) and application specificintegrated circuits (ASICs).

The example processing platform 210 of FIG. 2B includes a processor 212such as, for example, one or more microprocessors, controllers, and/orany suitable type of processor. The example processing platform 210 ofFIG. 2B includes memory (e.g., volatile memory, non-volatile memory) 214accessible by the processor 212 (e.g., via a memory controller). Theexample processor 212 interacts with the memory 214 to obtain, forexample, machine-readable instructions stored in the memory 214corresponding to, for example, the operations represented by theflowcharts of this disclosure. The example processor 212 may alsointeract with the memory 214 to obtain, or store, instructions relatedto the first imaging apparatus 202, the second imaging apparatus 204,and/or the illumination source 206. Additionally, or alternatively,machine-readable instructions corresponding to the example operationsdescribed herein may be stored on one or more removable media (e.g., acompact disc, a digital versatile disc, removable flash memory, etc.)that may be coupled to the processing platform 210 to provide access tothe machine-readable instructions stored thereon.

As illustrated in FIG. 2B, the first imaging apparatus 202 includes afirst imaging sensor(s) 202 b, and the second imaging apparatus 204includes a second imaging sensor(s) 204 b. As previously mentioned, eachof the first imaging apparatus 202 and the second imaging apparatus 204may also include shutters (not shown) that may electronically (ormechanically) expose the first imaging sensor(s) 202 b and/or the secondimaging sensor(s) 204 b to an external environment for image datacapture. Moreover, each of the first imaging sensor(s) 202 b and/or thesecond imaging sensor(s) 204 b may include one or more sensorsconfigured to capture image data corresponding to a target object, anindicia associated with the target object, and/or any other suitableimage data.

The example processing platform 210 of FIG. 2B also includes a networkinterface 216 to enable communication with other machines via, forexample, one or more networks. The example network interface 216includes any suitable type of communication interface(s) (e.g., wiredand/or wireless interfaces) configured to operate in accordance with anysuitable protocol(s). For example, in some embodiments, networkinginterface 216 may transmit data or information (e.g., imaging data,illumination pulse emission signals, etc., described herein) betweenremote processor(s) 222 and/or remote server 220, and processingplatform 210.

The example, processing platform 210 of FIG. 2B also includesinput/output (I/O) interfaces 218 to enable receipt of user input andcommunication of output data to the user.

FIG. 3A is a graph 300 illustrating a prior art activation sequence ofmultiple image sensors in a prior art barcode reader. As illustrated inFIG. 3A, the graph 300 includes a first line 302 representing anexposure sequence corresponding to a first imaging sensor operating as aglobal shutter imaging sensor, a second line 304 representing anexposure sequence corresponding to a second imaging sensor operating asa global shutter imaging sensor, and a third line 306 representing anillumination level provided by an illumination source. Generallyspeaking, the prior art activation sequence includes two periods 301 a,301 b, during which, the imaging sensors capture image data. Namely, thefirst exposure period 302 a for the first imaging sensor is during thefirst period 301 a, the second exposure period 304 a for the secondimaging sensor is during the second period 301 b, and both imagingsensors capture multiple image frames 302 a 1, 302 a 2, 304 a 1, 304 a 2during the respective exposure periods 302 a, 304 a operating as globalshutter imaging sensors.

At the beginning of the first period 301 a, the illumination source mayemit illumination, as represented by the increased level of illuminationat point 306 a on the third line 306. In the prior art activationsequence, the first imaging apparatus may trigger the first exposureperiod 302 a of the first imaging sensor based on this initialillumination emission by the illumination source. Accordingly, theexposure of the first imaging sensor increases simultaneously with theincreased level of illumination at point 306 a, and the first imagingsensor captures a set of image frames 302 a 1, 302 a 2 simultaneouslyduring the first exposure period 302 a. The first imaging apparatus maythen perform a sensor readout of the first imaging sensor after thefirst exposure period 302 a ends and before a subsequent exposure of thefirst imaging sensor begins (e.g., during the second period 301 b).

However, the exposure of the second imaging sensor elevates during thesecond period 301 b after the first imaging sensor, but while theillumination emitted from the illumination source is still present. Thesecond imaging sensor then captures a set of image frames 304 a 1, 304 a2 simultaneously during the second exposure period 304 a. The secondimaging apparatus may then then perform a sensor readout of the secondimaging sensor after the second exposure period 304 a ends and before asubsequent exposure of the second imaging sensor begins (e.g., duringand/or after the second period 301 b).

As previously mentioned, this prior art activation sequence suffers froma number of drawbacks. For example, global shutter imaging sensorsrequire dedicated image signal processors (ISPs), which increases thecomplexity and cost of conventional devices while minimizing the spaceavailable for additional features and increasing the overall devicesize. Rolling shutter imaging sensors typically include dedicated ISPs,which alleviates these issues completely. Moreover, such rolling shutterimaging sensors capture images with sufficient resolution for visualimaging applications (e.g., scan avoidance detection). Thus, themultiple global shutter imaging sensor configuration represented in theprior art activation sequence (and utilized in conventional devices)introduces unnecessary complexity, cost, and device size requirements inorder to accomplish both indicia scanning/decoding and visual imagingapplications.

However, as illustrated in FIGS. 3B-3F, the techniques of the presentdisclosure alleviate these issues associated with conventional systemsand activation sequences. For example, FIG. 3B is a graph 310illustrating a first exemplary activation sequence of the illuminationsource (e.g., illumination source 206), a first imaging sensor (e.g.,first imaging sensor 202), and a second imaging sensor (e.g., secondimaging sensor 204), in accordance with embodiments disclosed herein. Asillustrated in FIG. 3B, the graph 310 includes a first line 312representing the exposure of a first imaging sensor (e.g., first imagingsensor 202 b), a second line 314 representing the exposure of a secondimaging sensor (e.g., second imaging sensor 204 b), and a third line 316representing an illumination level provided by the illumination source206. As previously described, the illumination pulses emitted by theillumination source 206 may define a predetermined period, during which,the imaging apparatuses may expose and capture image data. One suchpredetermined period 316 b is illustrated in FIG. 3B by the perioddelineated by a beginning of a first exposure period 312 a of the firstimaging sensor and a beginning of a subsequent exposure period 312 b ofthe first imaging sensor. It should be understood that an “predeterminedperiod,” as described herein, may be any period of time during whichillumination from illumination pulses emitted by the illumination source206 is present. Moreover, an “exposure period,” as described herein, mayinclude image capture and image data readout as all/some of thecorresponding exposure period.

Generally speaking, the graph 310 representing the first exemplaryactivation sequence may indicate an interleaving of global shutterimaging sensor (e.g., the first imaging sensor represented on the firstline 312) exposure periods 312 a, 312 b and rolling shutter imagingsensor (e.g., the second imaging sensor represented on the second line314) exposure periods 314 a, 314 b. In particular, the graph 310representing the first exemplary activation sequence indicates that theexposure periods 314 a, 314 b of the rolling shutter imaging sensorbegin/end simultaneously and/or nearly simultaneously with adjacentexposure periods (e.g., a first exposure period 312 a and subsequentexposure period 312 b) corresponding to the global shutter imagingsensor. In this manner, the rolling imaging shutter may maximize thetime between adjacent global shutter imaging sensor exposure periods inorder to utilize the illumination emitted by the illumination sourceduring each exposure period (e.g., 314 a, 314 b) for image captureand/or data readout.

At the beginning of the predetermined period 316 b, the illuminationsource 206 may emit an illumination pulse, as represented by theincreased level of illumination at point 316 a on the first line 316. Inthe first exemplary activation sequence, the first imaging apparatus maytrigger the first exposure period 312 a based on this initialillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus 202 begins simultaneouslywith the increased level of illumination, such that the first imagingsensor captures multiple image frames 312 a 1, 312 a 2 simultaneouslyduring the first exposure period 312 a. When the first exposure period312 a ends, the second imaging apparatus may begin the second exposureperiod 314 a in order for the second imaging sensor to capture multipleimage frames 314 a 1, 314 a 2 sequentially during the second exposureperiod 314 a. Thus, as illustrated in FIG. 3B, the image data captureperformed by the first and second imaging sensors, is performed inaccordance with operation as a global shutter imaging sensor and arolling shutter imaging sensor, respectively.

In particular, as illustrated in FIG. 3B, the exposure periods 312 a,314 a of the respective imaging apparatuses are different from oneanother as well as the predetermined period 316 b, and the frame capturesequences of the two imaging sensors are also different. The firstexposure period 312 a for the first imaging sensor ends just beforeand/or nearly simultaneously with the beginning of the second exposureperiod 314 a, such that the imaging shutter of the first imaging sensorstops exposure of the first imaging sensor just before and/or nearlysimultaneously with the imaging shutter of the second imaging sensorbeginning exposure of the second imaging sensor. The first imagingapparatus may then begin an image readout for the first imaging sensor,which may extend from the end of the first exposure period 312 a to thebeginning of the subsequent exposure period 312 b and/or any suitableperiod there between. The image readout of the first imaging sensor(and/or the second imaging sensor) may include emptying the photositesof the first imaging sensor in order to begin analyzing the image datarepresented by the electrons stored in the respective photosites. Theimage readout for the first imaging sensor may occur for all imageframes 312 a 1, 312 a 2 simultaneously, as each image frame 312 a 1, 312a 2 is captured simultaneously. However, in certain aspects, the imagereadout for the first imaging sensor may occur in a sequential manner,such that the image frame 312 a 1 may be read from the correspondingphotosites of the first imaging sensor before the image frame 312 a 2 isread from the corresponding photosites of the first imaging sensor.

Further, as illustrated in FIG. 3B, the second imaging sensor maycapture image frames 314 a 1, 314 a 2 during a first subset 314 c 1 ofthe second exposure period 314 a. During a second subset 314 c 2 of thesecond exposure period 314 a (e.g., without image frame 314 a 1, 314 a 2captures), the second imaging apparatus may perform an image readout ofthe second imaging sensor in order to begin analyzing the image datacaptured by the second imaging sensor during the first subset 314 c 1 ofthe second exposure period 314 a. This second subset 314 c 2 of thesecond exposure period 314 a including the image readout of the secondimaging sensor may begin immediately following the capture of the lastimage frame (e.g., frames 314 a 1, 314 a 2) and may extend until the endof the second exposure period 314 a and/or any suitable period therebetween. Additionally, or alternatively, the image readout of the secondimaging sensor may begin for each image frame 314 a 1, 314 a 2 after theindividual image frame 314 a 1, 314 a 2 is captured. For example, thesecond imaging apparatus may begin an image readout of the image frame314 a 1 immediately following the capture of the image frame 314 a 1,such that the image frame 314 a 1 is being read from the correspondingphotosites of the second imaging sensor while the image frame 314 a 2 isbeing captured. In this manner, the image readout for the second imagingsensor may be performed sequentially, similar to the sequential captureof the image frames 314 a 1, 314 a 2.

In any event, the illumination level beginning at point 316 a that isprovided by the illumination pulse may last through the predeterminedperiod 316 b, such that subsequent exposure periods 312 b, 314 b forboth imaging sensors may be illuminated. The illumination pulse emittedby the illumination source may last any suitable duration (e.g., 5milliseconds (ms), 16 ms, 50 ms) in order to provide adequateillumination during both exposure periods 312 a, 314 a and any suitablenumber of subsequent exposure periods 312 b, 314 b in order to captureimage data sufficient to perform the image analysis techniques mentionedherein (e.g., barcode scanning/decoding, image recognition, etc.). Forexample, the illumination pulse emitted by the illumination source maylast over 32 ms in order to provide illumination for at least twoexposure periods for both imaging sensors. This first exemplaryactivation sequence illustrated by the graph 310 may repeat iterativelyany suitable number of times in order to capture any sufficient numberof images (e.g., frames 312 a 1, 312 a 2, 314 a 1, 314 a 2) for anysuitable image analysis purposes (e.g., indicia payload decoding, facialrecognition, scan avoidance detection, etc.).

FIG. 3C is a graph 320 illustrating a second exemplary activationsequence of the illumination source (e.g., illumination source 206), afirst imaging sensor (e.g., first imaging sensor 202), and a secondimaging sensor (e.g., second imaging sensor 204), in accordance withembodiments disclosed herein. As illustrated in FIG. 3C, the graph 320includes a first line 322 representing the exposure of a first imagingsensor (e.g., first imaging sensor 202 b), a second line 324representing the exposure of a second imaging sensor (e.g., secondimaging sensor 204 b), and a third line 326 representing an illuminationlevel provided by the illumination source 206. As previously described,the illumination pulses emitted by the illumination source 206 maydefine a predetermined period, during which, the imaging apparatuses mayexpose and capture image data. Several predetermined periods 326 a, 326b, 326 c, 326 d are illustrated in FIG. 3C and may correspond to severalexposure periods 322 a, 322 b, 324 a, 324 b of the first imaging sensorand the second imaging sensor.

Generally speaking, the graph 320 representing the second exemplaryactivation sequence may indicate an interleaving of global shutterimaging sensor (e.g., the first imaging sensor represented on the firstline 322) exposure periods 322 a, 322 b and rolling shutter imagingsensor (e.g., the second imaging sensor represented on the second line324) exposure periods 324 a, 324 b. In particular, the graph 320representing the second exemplary activation sequence indicates that theexposure periods 324 a, 324 b of the rolling shutter imaging sensor arecentered between adjacent exposure periods (e.g., a first exposureperiod 322 a and a third exposure period 322 b) corresponding to theglobal shutter imaging sensor. In this manner, the second imaging sensormay maximize the time between adjacent global shutter imaging sensorexposure periods while simultaneously minimizing the impact of theillumination emitted by the illumination source during those globalshutter imaging sensor exposure periods.

At the beginning of the first predetermined period 326 a, theillumination source 206 may emit an illumination pulse, as representedby the increased level of illumination on the third line 326. In thesecond exemplary activation sequence, the first imaging apparatus maytrigger the first exposure period 322 a based on this initialillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the first imaging sensor captures multiple image frames 322 a1, 322 a 2 simultaneously during the first exposure period 322 a. Whenthe first exposure period 322 a ends, the first predetermined period 326a may end shortly afterwards, such that the illumination emitted by theillumination source 206 also ends.

Subsequently, at the beginning of the second predetermined period 326 b,the illumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line326. In the second exemplary activation sequence, the second imagingapparatus may trigger the second exposure period 324 a based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the second imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the second imaging sensor captures multiple image frames 324 a1, 324 a 2 sequentially during the second exposure period 324 a. Whenthe second exposure period 324 a ends, the second predetermined period326 b may end shortly afterwards, such that the illumination emitted bythe illumination source 206 also ends.

At the beginning of the third predetermined period 326 c, theillumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line326. In the second exemplary activation sequence, the first imagingapparatus may trigger the third exposure period 322 b based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin shortly after theincreased level of illumination, such that the first imaging sensorcaptures multiple image frames 322 b 1, 322 b 2 simultaneously duringthe third exposure period 322 b. When the third exposure period 322 bends, the third predetermined period 326 c may end shortly afterwards,such that the illumination emitted by the illumination source 206 alsoends.

Thereafter, at the beginning of the fourth predetermined period 326 d,the illumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line326. In the second exemplary activation sequence, the second imagingapparatus may trigger the fourth exposure period 324 b based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the second imaging apparatus may begin simultaneouslyand/or nearly simultaneously after the increased level of illumination,such that the second imaging sensor captures multiple image frames 324 b1, 324 b 2 sequentially during the fourth exposure period 324 b. Whenthe fourth exposure period 324 b ends, the fourth predetermined period326 d may end simultaneously and/or shortly afterwards, such that theillumination emitted by the illumination source 206 also ends.

As illustrated in FIG. 3C, the exposure periods 322 a-b, 324 a-b of therespective imaging apparatuses are different from one another as well asthe predetermined periods 326 a, c, and the frame capture sequences ofthe two imaging sensors are also different. The first exposure period322 a for the first imaging sensor ends just before and/or nearlysimultaneously with the end of the first predetermined period 326 a. Thefirst imaging apparatus may then begin an image readout for the firstimaging sensor, which may extend from the end of the first exposureperiod 322 a to the beginning of the third exposure period 322 b and/orany suitable period there between. The image readout for the firstimaging sensor may occur for all image frames 322 a 1, 322 a 2simultaneously, as each image frame 322 a 1, 322 a 2 is capturedsimultaneously. However, in certain aspects, the image readout for thefirst imaging sensor may occur in a sequential manner, such that theimage frame 322 a 1 may be read from the corresponding photosites of thefirst imaging sensor before the image frame 322 a 2 is read from thecorresponding photosites of the first imaging sensor.

Further, as illustrated in FIG. 3C, the second imaging sensor maycapture image frames 324 a 1, 324 a 2 for a first subset 324 c 1 of thesecond exposure period 324 a. During a second subset 324 c 2 of thesecond exposure period 324 a (e.g., without image frame 324 a 1, 324 a 2captures), the second imaging apparatus may perform an image readout ofthe second imaging sensor in order to begin analyzing the image datacaptured by the second imaging sensor during the first subset 324 c 1 ofthe second exposure period 324 a. This second subset 324 c 2 of thesecond exposure period 324 a including the image readout of the secondimaging sensor may begin immediately following the capture of the lastimage frame (e.g., frames 324 a 1, 324 a 2) and may extend until the endof the second exposure period 324 a and/or any suitable period therebetween. Additionally, or alternatively, the image readout of the secondimaging sensor may begin for each image frame 324 a 1, 324 a 2 after theindividual image frame 324 a 1, 324 a 2 is captured. For example, thesecond imaging apparatus may begin an image readout of the image frame324 a 1 immediately following the capture of the image frame 324 a 1,such that the image frame 324 a 1 is being read from the correspondingphotosites of the second imaging sensor while the image frame 324 a 2 isbeing captured. In this manner, the image readout for the second imagingsensor may be performed sequentially, similar to the sequential captureof the image frames 324 a 1, 324 a 2.

Moreover, as illustrated in FIG. 3C, the illumination emitted by theillumination source 206 may overlap and/or slightly exceed theboundaries of any particular exposure period. For example, theillumination emitted by the illumination source defining the thirdpredetermined period 326 c may last longer than the corresponding thirdexposure period 322 b of the first imaging sensor. In this manner, thefirst imaging sensor may receive maximum illumination during the captureof each image frame 322 b 1, 322 b 2, and the illumination may end priorto the beginning of, and thereby not interfere with, the fourth exposureperiod 324 b of the second imaging sensor. Regardless, this secondexemplary activation sequence illustrated by the graph 320 may repeatiteratively any suitable number of times in order to capture anysufficient number of images (e.g., frames 322 a 1, 322 a 2, 322 b 1, 322b 2, 324 a 1, 324 a 2, 324 b 1, 324 b 2) for any suitable image analysispurposes (e.g., indicia payload decoding, facial recognition, scanavoidance detection, etc.).

FIG. 3D is a graph 330 illustrating a third exemplary activationsequence of the illumination source (e.g., illumination source 206), afirst imaging sensor (e.g., first imaging sensor 202), and a secondimaging sensor (e.g., second imaging sensor 204), in accordance withembodiments disclosed herein. As illustrated in FIG. 3D, the graph 330includes a first line 332 representing the exposure of a first imagingsensor (e.g., first imaging sensor 202 b), a second line 334representing the exposure of a second imaging sensor (e.g., secondimaging sensor 204 b), and a third line 336 representing an illuminationlevel provided by the illumination source 206. As previously described,the illumination pulses emitted by the illumination source 206 maydefine a predetermined period, during which, the imaging apparatuses mayexpose and capture image data. Two predetermined periods 336 a, 336 bare illustrated in FIG. 3D and may correspond to several exposureperiods 332 a, 332 b, 334 a, 334 b of the first imaging sensor and thesecond imaging sensor.

Generally speaking, the graph 330 representing the third exemplaryactivation sequence may indicate an interleaving of global shutterimaging sensor (e.g., the first imaging sensor represented on the firstline 332) exposure periods 332 a, 332 b, rolling shutter imaging sensor(e.g., the second imaging sensor represented on the second line 334)exposure period 334 a, and a subsequent global shutter imaging sensor(e.g., the second imaging sensor operating as a global shutter imagingsensor) exposure period 334 b. In particular, the graph 330 representingthe third exemplary activation sequence indicates that the secondimaging sensor is operating as a rolling shutter imaging sensor duringthe second exposure period 334 a and the second imaging sensor isoperating as a global shutter imaging sensor during the fourth exposureperiod 334 b. In this manner, the second imaging sensor may selectivelychange how image frame captures are performed during subsequent exposureperiods (e.g., exposure periods 334 a, 334 b) in order to optimize theimage frame captures for particular image analysis purposes. Forexample, capturing image frames while operating as a rolling shutterimaging sensor (e.g., during second exposure period 334 a) may beoptimal for image analysis techniques that are not very motionsensitive, and capturing image frames while operating as a globalshutter imaging sensor (e.g., during fourth exposure period 334 a) maybe optimal for image analysis techniques that are motion sensitive.

At the beginning of the first predetermined period 336 a, theillumination source 206 may emit an illumination pulse, as representedby the increased level of illumination on the third line 336. In thethird exemplary activation sequence, the first imaging apparatus maytrigger the first exposure period 332 a based on this initialillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the first imaging sensor captures multiple image frames 332 a1, 332 a 2 simultaneously during the first exposure period 332 a. Whenthe first exposure period 332 a ends, the first predetermined period 336a may continue, such that the illumination emitted by the illuminationsource 206 also continues into the second exposure period 334 a of thesecond imaging sensor.

Subsequently, the second imaging apparatus may trigger the secondexposure period 334 a still utilizing the illumination provided as partof the first predetermined period 336 a. Accordingly, the exposure ofthe second imaging apparatus may begin simultaneously and/or nearlysimultaneously with the end of the first exposure period 332 a, suchthat the second imaging sensor captures multiple image frames 334 a 1,334 a 2 sequentially during the second exposure period 334 a. When thesecond exposure period 334 a ends, the first predetermined period 336 amay continue, such that the illumination emitted by the illuminationsource 206 also continues into the third exposure period 332 b of thefirst imaging sensor.

Thereafter, the first imaging apparatus may trigger the third exposureperiod 332 b still utilizing the illumination provided as part of thefirst predetermined period 336 a. Accordingly, the exposure of the firstimaging apparatus may simultaneously and/or nearly simultaneously withthe end of the second exposure period 334 a, such that the first imagingsensor captures multiple image frames 332 b 1, 332 b 2 simultaneouslyduring the third exposure period 332 b. When the third exposure period332 b ends, the first predetermined period 336 a may end shortlyafterwards, such that the illumination emitted by the illuminationsource 206 also ends.

At the beginning of the second predetermined period 336 b, theillumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line336. In the third exemplary activation sequence, the second imagingapparatus may trigger the fourth exposure period 334 b based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the second imaging apparatus may begin simultaneouslyand/or nearly simultaneously after the increased level of illumination,such that the second imaging sensor captures multiple image frames 334 b1, 334 b 2 simultaneously during the fourth exposure period 334 b. Whenthe fourth exposure period 334 b ends, the second predetermined period336 b may end simultaneously and/or shortly afterwards, such that theillumination emitted by the illumination source 206 also ends.

As illustrated in FIG. 3D, the exposure periods 334 a, 334 b of thesecond imaging sensor are different from one another. Namely, the secondexposure period 334 a represents the second imaging sensor operating asa rolling shutter imaging sensor, and the fourth exposure period 334 brepresents the second imaging sensor operating as a global shutterimaging sensor. As previously mentioned, selectively operating thesecond imaging sensor as a rolling/global shutter imaging sensor enablesthe second imaging sensor to capture image data in accordance with theparticular imaging requirements of the image analysis intended to beperformed on the captured image frames 334 a 1, 334 a 2, 334 b 1, 334 b2. Moreover, as illustrated in FIG. 3D, the illumination source 206 maybe configured to emit illumination suitable for such a change in theoperation of the second imaging sensor. The first predetermined period336 a represents illumination lasting through each of the first exposureperiod 332 a, the second exposure period 334 a, and the third exposureperiod 332 b. When the second imaging sensor begins operating as aglobal shutter imaging sensor, the illumination source 206 emitsillumination lasting the fourth exposure period 334 b, as illustrated bythe second predetermined period 336.

Of course, this third exemplary activation sequence illustrated by thegraph 330 may repeat iteratively any suitable number of times in orderto capture any sufficient number of images (e.g., frames 332 a 1, 332 a2, 332 b 1, 332 b 2, 334 a 1, 334 a 2, 334 b 1, 334 b 2) for anysuitable image analysis purposes (e.g., indicia payload decoding, facialrecognition, scan avoidance detection, etc.).

FIG. 3E is a graph 340 illustrating a fourth exemplary activationsequence of the illumination source (e.g., illumination source 206), afirst imaging sensor (e.g., first imaging sensor 202), and a secondimaging sensor (e.g., second imaging sensor 204), in accordance withembodiments disclosed herein. As illustrated in FIG. 3E, the graph 340includes a first line 342 representing the exposure of a first imagingsensor (e.g., first imaging sensor 202 b), a second line 344representing the exposure of a second imaging sensor (e.g., secondimaging sensor 204 b), and a third line 346 representing an illuminationlevel provided by the illumination source 206. As previously described,the illumination pulses emitted by the illumination source 206 maydefine a predetermined period, during which, the imaging apparatuses mayexpose and capture image data. One such predetermined period 346 a isillustrated in FIG. 3E and may correspond to several exposure periods342 a, 342 b, 344 a, 344 b of the first imaging sensor and the secondimaging sensor.

Generally speaking, the graph 340 representing the fourth exemplaryactivation sequence may indicate an interleaving of global shutterimaging sensor (e.g., the first imaging sensor represented on the firstline 342) exposure periods 342 a, 342 b and rolling shutter imagingsensor (e.g., the second imaging sensor represented on the second line334) exposure periods 344 a, 344 b. In particular, the graph 340representing the fourth exemplary activation sequence indicates that thesecond exposure period 344 a and the fourth exposure period 344 b beginwithin the first exposure period 342 a and the third exposure period 342b, respectively. In this manner, the second imaging sensor may begincapturing image data at least partially while the first imaging sensoris also capturing image data.

At the beginning of the first predetermined period 346 a, theillumination source 206 may emit an illumination pulse, as representedby the increased level of illumination on the third line 346. In thefourth exemplary activation sequence, the first imaging apparatus maytrigger the first exposure period 342 a based on this initialillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the first imaging sensor captures multiple image frames 342 a1, 342 a 2 simultaneously during the first exposure period 342 a. Whenthe first exposure period 342 a ends, the first predetermined period 346a may continue, such that the illumination emitted by the illuminationsource 206 also continues into the second exposure period 344 a of thesecond imaging sensor.

Subsequently, the second imaging apparatus may trigger the secondexposure period 344 a still utilizing the illumination provided as partof the first predetermined period 346 a, and at least partially duringthe first exposure period 342 a. Accordingly, the exposure of the secondimaging apparatus may begin prior to the end of the first exposureperiod 342 a, and the second imaging sensor may capture multiple imageframes 344 a 1, 344 a 2 sequentially during the second exposure period344 a. When the second exposure period 344 a ends, the firstpredetermined period 346 a may continue, such that the illuminationemitted by the illumination source 206 also continues into the thirdexposure period 342 b of the first imaging sensor.

Thereafter, the first imaging apparatus may trigger the third exposureperiod 342 b still utilizing the illumination provided as part of thefirst predetermined period 346 a. Accordingly, the exposure of the firstimaging apparatus may simultaneously and/or nearly simultaneously withthe end of the second exposure period 344 a, and the first imagingsensor may capture multiple image frames 342 b 1, 342 b 2 simultaneouslyduring the third exposure period 342 b. When the third exposure period342 b ends, the first predetermined period 346 a may still continue,such that the illumination emitted by the illumination source 206 alsocontinues into the fourth exposure period 344 b of the second imagingsensor.

Further, in the fourth exemplary activation sequence, the second imagingapparatus may trigger the fourth exposure period 344 b still utilizingthe illumination provided as part of the first predetermined period 346a, and at least partially during the third exposure period 342 b.Accordingly, the exposure of the second imaging apparatus may beginprior to the end of the third exposure period 342 b, and the secondimaging sensor may capture multiple image frames 344 b 1, 344 b 2sequentially during the fourth exposure period 344 b. When the fourthexposure period 344 b ends, the first predetermined period 346 a may endsimultaneously and/or shortly afterwards, such that the illuminationemitted by the illumination source 206 also ends.

As illustrated in FIG. 3E, the illumination source 206 may be configuredto emit illumination to provide illumination for each of the firstexposure period 342 a, the second exposure period 344 a, the thirdexposure period 342 b, and the fourth exposure period 344 b proceedingin sequence. Moreover, this fourth exemplary activation sequenceillustrated by the graph 340 may repeat iteratively any suitable numberof times in order to capture any sufficient number of images (e.g.,frames 342 a 1, 342 a 2, 342 b 1, 342 b 2, 344 a 1, 344 a 2, 344 b 1,344 b 2) for any suitable image analysis purposes (e.g., indicia payloaddecoding, facial recognition, scan avoidance detection, etc.).

FIG. 3F is a graph 350 illustrating a fifth exemplary activationsequence of the illumination source (e.g., illumination source 206), afirst imaging sensor (e.g., first imaging sensor 202), and a secondimaging sensor (e.g., second imaging sensor 204), in accordance withembodiments disclosed herein. As illustrated in FIG. 3C, the graph 350includes a first line 352 representing the exposure of a first imagingsensor (e.g., first imaging sensor 202 b), a second line 354representing the exposure of a second imaging sensor (e.g., secondimaging sensor 204 b), and a third line 356 representing an illuminationlevel provided by the illumination source 206. As previously described,the illumination pulses emitted by the illumination source 206 maydefine a predetermined period, during which, the imaging apparatuses mayexpose and capture image data. Several predetermined periods 356 a, 356b, 356 c, 356 d are illustrated in FIG. 3F and may correspond to severalexposure periods 352 a, 352 b, 354 a, 354 b of the first imaging sensorand the second imaging sensor.

Generally speaking, the graph 350 representing the fifth exemplaryactivation sequence may indicate an interleaving of global shutterimaging sensor (e.g., the first imaging sensor represented on the firstline 352) exposure periods 352 a, 352 b and rolling shutter imagingsensor (e.g., the second imaging sensor represented on the second line354) exposure periods 354 a, 354 b. In particular, the graph 350representing the fifth exemplary activation sequence indicates that theexposure periods 354 a, 354 b of the rolling shutter imaging sensor arecentered between adjacent exposure periods (e.g., a first exposureperiod 352 a and a third exposure period 352 b) corresponding to theglobal shutter imaging sensor. In this manner, the second imaging sensormay maximize the time between adjacent global shutter imaging sensorexposure periods while simultaneously minimizing the impact of theillumination emitted by the illumination source during those globalshutter imaging sensor exposure periods. Further, the illuminationemitted by the illumination source 206 (e.g., predetermined periods 356a-d) may synchronize exactly with each of the exposure periods (e.g.,352 a, 352 b, 354 a, 354 b).

At the beginning of the first predetermined period 356 a, theillumination source 206 may emit an illumination pulse, as representedby the increased level of illumination on the third line 356. In thefifth exemplary activation sequence, the first imaging apparatus maytrigger the first exposure period 352 a based on this initialillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the first imaging sensor captures multiple image frames 352 a1, 352 a 2 simultaneously during the first exposure period 352 a. Whenthe first exposure period 352 a ends, the first predetermined period 356a may end simultaneously, such that the illumination emitted by theillumination source 206 also ends.

Subsequently, at the beginning of the second predetermined period 356 b,the illumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line356. In the fifth exemplary activation sequence, the second imagingapparatus may trigger the second exposure period 354 a based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the second imaging apparatus may begin simultaneouslyand/or nearly simultaneously with the increased level of illumination,such that the second imaging sensor captures multiple image frames 354 a1, 354 a 2 sequentially during the second exposure period 354 a. Whenthe second exposure period 354 a ends, the second predetermined period356 b may end simultaneously, such that the illumination emitted by theillumination source 206 also ends.

At the beginning of the third predetermined period 356 c, theillumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line356. In the fifth exemplary activation sequence, the first imagingapparatus may trigger the third exposure period 352 b based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the first imaging apparatus may begin simultaneouslywith the increased level of illumination, such that the first imagingsensor captures multiple image frames 352 b 1, 352 b 2 simultaneouslyduring the third exposure period 352 b. When the third exposure period352 b ends, the third predetermined period 356 c may end simultaneously,such that the illumination emitted by the illumination source 206 alsoends.

Thereafter, at the beginning of the fourth predetermined period 356 d,the illumination source 206 may emit another illumination pulse, asrepresented by the increased level of illumination on the third line356. In the fifth exemplary activation sequence, the second imagingapparatus may trigger the fourth exposure period 354 b based on thisillumination pulse emission by the illumination source 206. Accordingly,the exposure of the second imaging apparatus may begin simultaneouslyand/or nearly simultaneously after the increased level of illumination,such that the second imaging sensor captures multiple image frames 354 b1, 354 b 2 sequentially during the fourth exposure period 354 b. Whenthe fourth exposure period 354 b ends, the fourth predetermined period356 d may end simultaneously, such that the illumination emitted by theillumination source 206 also ends.

As illustrated in FIG. 3F, the first exposure period 352 a for the firstimaging sensor ends simultaneously with the end of the firstpredetermined period 356 a. The first imaging apparatus may then beginan image readout for the first imaging sensor, which may extend from theend of the first exposure period 352 a to the beginning of the thirdexposure period 352 b and/or any suitable period there between. Theimage readout for the first imaging sensor may occur for all imageframes 352 a 1, 352 a 2 simultaneously, as each image frame 352 a 1, 352a 2 is captured simultaneously. However, in certain aspects, the imagereadout for the first imaging sensor may occur in a sequential manner,such that the image frame 352 a 1 may be read from the correspondingphotosites of the first imaging sensor before the image frame 352 a 2 isread from the corresponding photosites of the first imaging sensor.

Further, as illustrated in FIG. 3F, the second imaging sensor maycapture image frames 354 a 1, 354 a 2 for a first subset 354 c 1 of thesecond exposure period 354 a. During a second subset 354 c 2 of thesecond exposure period 354 a (e.g., without image frame 354 a 1, 354 a 2captures), the second imaging apparatus may perform an image readout ofthe second imaging sensor in order to begin analyzing the image datacaptured by the second imaging sensor during the first subset 354 c 1 ofthe second exposure period 354 a. This second subset 354 c 2 of thesecond exposure period 354 a including the image readout of the secondimaging sensor may begin immediately following the capture of the lastimage frame (e.g., frames 354 a 1, 354 a 2) and may extend until the endof the second exposure period 354 a and/or any suitable period therebetween. Additionally, or alternatively, the image readout of the secondimaging sensor may begin for each image frame 354 a 1, 354 a 2 after theindividual image frame 354 a 1, 354 a 2 is captured. For example, thesecond imaging apparatus may begin an image readout of the image frame354 a 1 immediately following the capture of the image frame 354 a 1,such that the image frame 354 a 1 is being read from the correspondingphotosites of the second imaging sensor while the image frame 354 a 2 isbeing captured. In this manner, the image readout for the second imagingsensor may be performed sequentially, similar to the sequential captureof the image frames 354 a 1, 354 a 2. Moreover, as illustrated in FIG.3F, the illumination emitted by the illumination source 206 maysynchronize exactly and/or nearly exactly with the boundaries of anyparticular exposure period. For example, the illumination emitted by theillumination source defining the third predetermined period 356 c maylast exactly as long as the corresponding third exposure period 352 b ofthe first imaging sensor. In this manner, the first imaging sensor mayreceive maximum illumination during the capture of each image frame 352b 1, 352 b 2, and the illumination may end simultaneously with the endof the corresponding third exposure period 352 b. Regardless, this fifthexemplary activation sequence illustrated by the graph 350 may repeatiteratively any suitable number of times in order to capture anysufficient number of images (e.g., frames 352 a 1, 352 a 2, 352 b 1, 352b 2, 354 a 1, 354 a 2, 354 b 1, 354 b 2) for any suitable image analysispurposes (e.g., indicia payload decoding, facial recognition, scanavoidance detection, etc.).

Moreover, it should be appreciated that the exemplary activationsequences described herein are for the purposes of discussion only, andthat the shared illumination source 206 and imaging apparatuses 202, 204and corresponding imaging sensors 202 b, 204 b may activate in anysuitable combination(s) of the image capture durations and/or exposureperiods discussed herein.

FIG. 4 illustrates an example method 400 for capturing image data by afirst imaging sensor and a second imaging sensor using illuminationemitted by an illumination source, in accordance with embodimentsdisclosed herein. The method 400 includes emitting illumination lastinga predetermined period (block 402). The illumination pulse may beemitted by an illumination source (e.g., illumination source 206), andin certain embodiments, the illumination source may be configured toemit an illumination pulse that provides illumination lasting thepredetermined period.

The method 400 further includes exposing a first imaging sensor for afirst period that overlaps at least partially with the predeterminedperiod, where the first imaging sensor operates as a global shutterimaging sensor (block 404). In certain embodiments, an initial exposureof the first imaging sensor may be within 2 milliseconds (ms) of abeginning of the predetermined period, and an initial exposure of thesecond imaging sensor may be within 2 ms of an end of the first period.

The method 400 further includes capturing, by the first imaging sensor,first image data representative of an environment appearing within afield of view (FOV) of the first imaging sensor during the first period(block 406). In some embodiments, a first sensor readout period of thefirst imaging sensor and a second sensor readout period of the secondimaging sensor take place at least partially within the predeterminedperiod.

The method 400 further includes exposing a second imaging sensor for asecond period that overlaps at least partially with the predeterminedperiod and is different from the first period, where the second imagingsensor operates as a rolling shutter imaging sensor (block 408). Incertain embodiments, the second period at least partially overlaps withthe first period (e.g., the second exposure period 344 a overlappingpartially with the first exposure period 342 a of FIG. 3E). In someembodiments, the second period corresponds with a central period of thepredetermined period that does not include the first period (e.g., thesecond exposure period 324 a and the fourth exposure period 324 b ofFIG. 3C).

In some embodiments, the first period begins within 2 milliseconds (ms)of the second period, the FOV of the second imaging sensor is largerthan the FOV of the first imaging sensor, and a portion of the emittedillumination is clipped to avoid illuminating a set of initially exposedsensor rows of the second imaging sensor that are along an edge of theFOV of the second imaging sensor. For example, the illumination sourcemay include at least one of a baffle or a field stop that is configuredto clip the emitted illumination, and/or the illumination source may beconfigured to limit the illumination pulse so that it does not occurduring an initial portion of the second period.

In certain embodiments, the first period begins within 2 milliseconds(ms) of an end of the second period, the FOV of the second imagingsensor is larger than the FOV of the first imaging sensor, and a portionof the emitted illumination is clipped to avoid illuminating a set offinally exposed sensor rows of the second imaging sensor that are alongan edge of the FOV of the second imaging sensor. Similar to the priorembodiments, the illumination source may include at least one of abaffle or a field stop that is configured to clip the emittedillumination, and/or the illumination source may be configured to limitthe illumination pulse so that it does not occur during a final portionof the second period.

The method 400 further includes capturing, by the second imaging sensor,second image data representative of an environment appearing within aFOV of the second imaging sensor (block 410). In some embodiments, abeginning of a subsequent image data capture of the first imaging sensoris within 2 milliseconds (ms) of an end of the second period (e.g.,third exposure period 332 b of FIG. 3D).

In certain embodiments, a first imaging apparatus that includes thefirst imaging sensor may receive a delay signal to delay exposure of thefirst imaging sensor until the second imaging sensor is not exposed. Forexample, the first imaging apparatus may receive this delay signal inresponse (or as a result of) the second period ending at least partiallyoutside of the predetermined period.

In some embodiments, the second imaging sensor is further configured tocapture subsequent image data representative of the environmentappearing within the FOV of the second imaging sensor during asubsequent period that is different from the second period, the secondimaging sensor operating as a global shutter imaging sensor during thesubsequent period. For example, as illustrated in FIG. 3D, the secondimaging sensor operates as a rolling shutter imaging sensor during asecond exposure period 334 a, and the second imaging sensor operates asa global shutter imaging sensor during a fourth exposure period 334 b.

In certain embodiments, the first period begins within 2 milliseconds(ms) of the second period, and image data captured by a set of initiallyexposed sensor rows of the second imaging sensor is discarded during asecond imaging sensor readout period within the predetermined period.

The above description refers to a block diagram of the accompanyingdrawings. Alternative implementations of the example represented by theblock diagram includes one or more additional or alternative elements,processes and/or devices. Additionally, or alternatively, one or more ofthe example blocks of the diagram may be combined, divided, re-arrangedor omitted. Components represented by the blocks of the diagram areimplemented by hardware, software, firmware, and/or any combination ofhardware, software and/or firmware. In some examples, at least one ofthe components represented by the blocks is implemented by a logiccircuit. As used herein, the term “logic circuit” is expressly definedas a physical device including at least one hardware componentconfigured (e.g., via operation in accordance with a predeterminedconfiguration and/or via execution of stored machine-readableinstructions) to control one or more machines and/or perform operationsof one or more machines. Examples of a logic circuit include one or moreprocessors, one or more coprocessors, one or more microprocessors, oneor more controllers, one or more digital signal processors (DSPs), oneor more application specific integrated circuits (ASICs), one or morefield programmable gate arrays (FPGAs), one or more microcontrollerunits (MCUs), one or more hardware accelerators, one or morespecial-purpose computer chips, and one or more system-on-a-chip (SoC)devices. Some example logic circuits, such as ASICs or FPGAs, arespecifically configured hardware for performing operations (e.g., one ormore of the operations described herein and represented by theflowcharts of this disclosure, if such are present). Some example logiccircuits are hardware that executes machine-readable instructions toperform operations (e.g., one or more of the operations described hereinand represented by the flowcharts of this disclosure, if such arepresent). Some example logic circuits include a combination ofspecifically configured hardware and hardware that executesmachine-readable instructions. The above description refers to variousoperations described herein and flowcharts that may be appended heretoto illustrate the flow of those operations. Any such flowcharts arerepresentative of example methods disclosed herein. In some examples,the methods represented by the flowcharts implement the apparatusrepresented by the block diagrams. Alternative implementations ofexample methods disclosed herein may include additional or alternativeoperations. Further, operations of alternative implementations of themethods disclosed herein may combined, divided, re-arranged or omitted.In some examples, the operations described herein are implemented bymachine-readable instructions (e.g., software and/or firmware) stored ona medium (e.g., a tangible machine-readable medium) for execution by oneor more logic circuits (e.g., processor(s)). In some examples, theoperations described herein are implemented by one or moreconfigurations of one or more specifically designed logic circuits(e.g., ASIC(s)). In some examples the operations described herein areimplemented by a combination of specifically designed logic circuit(s)and machine-readable instructions stored on a medium (e.g., a tangiblemachine-readable medium) for execution by logic circuit(s).

As used herein, each of the terms “tangible machine-readable medium,”“non-transitory machine-readable medium” and “machine-readable storagedevice” is expressly defined as a storage medium (e.g., a platter of ahard disk drive, a digital versatile disc, a compact disc, flash memory,read-only memory, random-access memory, etc.) on which machine-readableinstructions (e.g., program code in the form of, for example, softwareand/or firmware) are stored for any suitable duration of time (e.g.,permanently, for an extended period of time (e.g., while a programassociated with the machine-readable instructions is executing), and/ora short period of time (e.g., while the machine-readable instructionsare cached and/or during a buffering process)). Further, as used herein,each of the terms “tangible machine-readable medium,” “non-transitorymachine-readable medium” and “machine-readable storage device” isexpressly defined to exclude propagating signals. That is, as used inany claim of this patent, none of the terms “tangible machine-readablemedium,” “non-transitory machine-readable medium,” and “machine-readablestorage device” can be read to be implemented by a propagating signal.

In the foregoing specification, specific embodiments have beendescribed. However, one of ordinary skill in the art appreciates thatvarious modifications and changes can be made without departing from thescope of the invention as set forth in the claims below. Accordingly,the specification and figures are to be regarded in an illustrativerather than a restrictive sense, and all such modifications are intendedto be included within the scope of present teachings. Additionally, thedescribed embodiments/examples/implementations should not be interpretedas mutually exclusive, and should instead be understood as potentiallycombinable if such combinations are permissive in any way. In otherwords, any feature disclosed in any of the aforementionedembodiments/examples/implementations may be included in any of the otheraforementioned embodiments/examples/implementations.

The benefits, advantages, solutions to problems, and any element(s) thatmay cause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeatures or elements of any or all the claims. The claimed invention isdefined solely by the appended claims including any amendments madeduring the pendency of this application and all equivalents of thoseclaims as issued.

Moreover, in this document, relational terms such as first and second,top and bottom, and the like may be used solely to distinguish oneentity or action from another entity or action without necessarilyrequiring or implying any actual such relationship or order between suchentities or actions. The terms “comprises,” “comprising,” “has”,“having,” “includes”, “including,” “contains”, “containing” or any othervariation thereof, are intended to cover a non-exclusive inclusion, suchthat a process, method, article, or apparatus that comprises, has,includes, contains a list of elements does not include only thoseelements but may include other elements not expressly listed or inherentto such process, method, article, or apparatus. An element proceeded by“comprises . . . a”, “has . . . a”, “includes . . . a”, “contains . . .a” does not, without more constraints, preclude the existence ofadditional identical elements in the process, method, article, orapparatus that comprises, has, includes, contains the element. The terms“a” and “an” are defined as one or more unless explicitly statedotherwise herein. The terms “substantially”, “essentially”,“approximately”, “about” or any other version thereof, are defined asbeing close to as understood by one of ordinary skill in the art, and inone non-limiting embodiment the term is defined to be within 10%, inanother embodiment within 5%, in another embodiment within 1% and inanother embodiment within 0.5%. The term “coupled” as used herein isdefined as connected, although not necessarily directly and notnecessarily mechanically. A device or structure that is “configured” ina certain way is configured in at least that way, but may also beconfigured in ways that are not listed.

The Abstract of the Disclosure is provided to allow the reader toquickly ascertain the nature of the technical disclosure. It issubmitted with the understanding that it will not be used to interpretor limit the scope or meaning of the claims. In addition, in theforegoing Detailed Description, it can be seen that various features aregrouped together in various embodiments for the purpose of streamliningthe disclosure. This method of disclosure is not to be interpreted asreflecting an intention that the claimed embodiments require morefeatures than are expressly recited in each claim. Rather, as thefollowing claims reflect, inventive subject matter may lie in less thanall features of a single disclosed embodiment. Thus, the followingclaims are hereby incorporated into the Detailed Description, with eachclaim standing on its own as a separately claimed subject matter.

1. An imaging system for reading and/or decoding indicia, the imagingsystem comprising: an illumination source configured to emitillumination lasting a predetermined period; a first imaging sensorconfigured to capture first image data representative of an environmentappearing within a field of view (FOV) of the first imaging sensorduring a first period that overlaps at least partially with thepredetermined period, the first imaging sensor operating as a globalshutter imaging sensor; and a second imaging sensor configured tocapture second image data representative of an environment appearingwithin a FOV of the second imaging sensor during a second period thatoverlaps at least partially with the predetermined period and isdifferent from the first period, the second imaging sensor operating asa rolling shutter imaging sensor.
 2. The imaging system of claim 1,wherein an initial exposure of the first imaging sensor is within 2milliseconds (ms) of a beginning of the predetermined period, and aninitial exposure of the second imaging sensor is within 2 ms of an endof the first period.
 3. The imaging system of claim 1, wherein a firstsensor readout period of the first imaging sensor and a second sensorreadout period of the second imaging sensor take place at leastpartially within the predetermined period.
 4. The imaging system ofclaim 1, wherein a beginning of a subsequent image data capture of thefirst imaging sensor is within 2 milliseconds (ms) of an end of thesecond period.
 5. The imaging system of claim 1, further comprising: afirst imaging apparatus that includes the first imaging sensor, andwherein, responsive to the second period ending at least partiallyoutside of the predetermined period, the first imaging apparatusreceives a delay signal to delay exposure of the first imaging sensoruntil the second imaging sensor is not exposed.
 6. The imaging system ofclaim 1, wherein the second imaging sensor is further configured tocapture subsequent image data representative of the environmentappearing within the FOV of the second imaging sensor during asubsequent period that is different from the second period, the secondimaging sensor operating as a global shutter imaging sensor during thesubsequent period.
 7. The imaging system of claim 1, wherein the secondperiod at least partially overlaps with the first period.
 8. The imagingsystem of claim 1, wherein the second period corresponds with a centralperiod of the predetermined period that does not include the firstperiod.
 9. The imaging system of claim 1, wherein the first periodbegins within 2 milliseconds (ms) of the second period, and image datacaptured by a set of initially exposed sensor rows of the second imagingsensor is discarded during a second imaging sensor readout period withinthe predetermined period.
 10. The imaging system of claim 1, wherein thefirst period begins within 2 milliseconds (ms) of the second period, theFOV of the second imaging sensor is larger than the FOV of the firstimaging sensor, and a portion of the emitted illumination is clipped toavoid illuminating a set of initially exposed sensor rows of the secondimaging sensor that are along an edge of the FOV of the second imagingsensor.
 11. The imaging system of claim 1, wherein the first periodbegins within 2 milliseconds (ms) of an end of the second period, theFOV of the second imaging sensor is larger than the FOV of the firstimaging sensor, and a portion of the emitted illumination is clipped toavoid illuminating a set of finally exposed sensor rows of the secondimaging sensor that are along an edge of the FOV of the second imagingsensor.
 12. A tangible machine-readable medium comprising instructionsfor reading and/or decoding indicia that, when executed, cause a machineto at least: emit illumination lasting a predetermined period; expose afirst imaging sensor for a first period that overlaps at least partiallywith the predetermined period, the first imaging sensor operating as aglobal shutter imaging sensor; capture, by the first imaging sensor,first image data representative of an environment appearing within afield of view (FOV) of the first imaging sensor during the first period;expose a second imaging sensor for a second period that overlaps atleast partially with the predetermined period and is different from thefirst period, the second imaging sensor operating as a rolling shutterimaging sensor; and capture, by the second imaging sensor, second imagedata representative of an environment appearing within a FOV of thesecond imaging sensor.
 13. The tangible machine-readable medium of claim12, wherein the instructions, when executed, further cause the machineto at least: begin exposing the first imaging sensor within 2milliseconds (ms) of a beginning of the predetermined period; and beginexposing the second imaging sensor within 2 ms of an end of the firstperiod.
 14. The tangible machine-readable medium of claim 12, whereinthe instructions, when executed, further cause the machine to at least:cause a first sensor readout period of the first imaging sensor and asecond sensor readout period of the second sensor to take place at leastpartially within the predetermined period.
 15. The tangiblemachine-readable medium of claim 12, wherein the instructions, whenexecuted, further cause the machine to at least: begin capturing, by thefirst imaging sensor, subsequent image data within 2 milliseconds (ms)of an end of the second period.
 16. The tangible machine-readable mediumof claim 12, wherein the instructions, when executed, further cause themachine to at least: responsive to the second period ending at leastpartially outside of the predetermined period, delay exposure of thefirst imaging sensor until the second imaging sensor is not exposed. 17.The tangible machine-readable medium of claim 12, wherein theinstructions, when executed, further cause the machine to at least:cause the second imaging sensor to capture subsequent image datarepresentative of the environment appearing within the FOV of the secondimaging sensor during a subsequent period that is different from thesecond period, the second imaging sensor operating as a global shutterimaging sensor during the subsequent period.
 18. The tangiblemachine-readable medium of claim 12, wherein the instructions, whenexecuted, further cause the machine to at least: expose the secondimaging sensor at least partially during the first period, such that thesecond period at least partially overlaps with the first period.
 19. Thetangible machine-readable medium of claim 12, wherein the instructions,when executed, further cause the machine to at least: expose the secondimaging sensor such that the second period corresponds with a centralperiod of the predetermined period that does not include the firstperiod.
 20. The tangible machine-readable medium of claim 12, whereinthe instructions, when executed, further cause the machine to at least:cause the first period to begin within 2 milliseconds (ms) of the secondperiod; and discard image data captured by a set of initially exposedsensor rows of the second imaging sensor during a second sensor readoutperiod within the predetermined period.